2-substituted aminothiazoles



United States Patent O 3,467,666 Z-SUBSTITUTED AMINOTHIAZOLES MartinDexter, Briarcliif Manor, and John Denon Spivaclr, Spring Valley, N.Y.,assignors to Geigy Chemical Corporation, Ardsley, N.Y., a corporation ofNew York No Drawing. Continuation of application Ser. No. 487,348, Aug.5, 1965. This application Nov. 7, 1966, Ser. No. 592,278 The portion ofthe term of the patent subsequent to June 24. 1982, has been disclaimedInt. Cl. C07d 91/46, 91 /34; C08f 45/60 US. Cl. 260306.8 8 ClaimsABSTRACT OF THE DISCLOSURE Z-substituted aminothiazoles, such as2-arylamino-4- arylthiazoles, Z-acenaphthylamino substituted thiazoles,2,2 imino bis (4-substituted thiazoles) 2-arylamino-4- alkylthiazoles,2-arylamino-5-alkylthiazoles, 2-arylaminotetrahydrobenzothiazoles, andbiphenylene-bis-(2-amino- 4-substituted thiazoles), are disclosed asuseful for stabilizing organic material normally subject to oxidativeand/or light, or thermal induced deterioration. Organic materialsstabilized include polyolefinic materials such as polypropylene, fatsincluding oils of animal and vegetable origin, gasolines, jet fuel,waxes and the like. A particularly elfective stabilizer for polyolefinicmaterial such as polypropylene is 2,2-imino bis 4(p-t-butylphenyl)-thiazole. 2-(paminoanilino)-4-t-butylthiazole is aneffective stabilizer for paraflin waX. Z-(m-aminoanilino)-4-tbutylthiazole is an effective stabilizer for polyethylene and aldehydes.

CROSS REFERENCES TO RELATED APPLICATIONS This application is acontinuation application of Ser. No. 487,348 filed Aug. 5, 1965, nowU.S. Patent No. 3,299,087 which in turn is a divisional of applicationSer. No. 104,805 filed Apr. 24, 1961, now abandoned, which is acontinuation-in-part of application Ser. No. 28,839 filed May 13, 1960,now abandoned. US. application Ser. No. 239,783 filed Nov. 23, 1962, nowUS. Patent No. 3,228,888, is a divisional application of said Ser. No.28,839. US. application Ser. No. 253,097 filed Dec. 27, 1962, now US.Patent No. 3,112,225 is a divisional application of said Ser. No.104,805. US. application Ser. No. 253,016 filed Dec. 28, 1962, now US.Patent No. 2,301,409 is also a divisional application of said Ser. No.104,805.

THE INVENTION This invention relates to novel substituted thiazolecompounds. In one aspect thereof, the invention comprises a first classof new substituted thiazole compounds of the formula:

5 I wherein:

R represents alkyl having greater than 3 carbon atoms,

' preferably from 4 to 8 carbon atoms, e.g. butyl, pentyl, hexyl,heptyl, octyl, nonyl, decyl, hendecyl, dodecyl, pentadecyl, octadecyl,etc., substituted aryl, preferably alkylphenyl, especially alkylphenylhaving from 7 to 24 carbon atoms, e.g. tolyl, ethylphenyl, propylphenyl,butylphenyl, pentylphenyl, hexylphenyl, heptylphenyl, octylphenyl,nonylphenyl, decylphenyl, hendecylphenyl, dodecylphenyl,pentadecylphenyl, octadecylphenyl, etc.;

R represents hydrogen;

R and R when taken jointly, represent 3,467,666 Patented Sept. 16, 1969and ' X represents aryl, preferably napthyl, substituted aryl wherein Ris as above defined. A second class of new substituted thiazolescomprises compounds of the formula:

i i Y-N-o 0H.

R4 S H wherein R represents alkyl, such as e.g. methyl, ethyl, propyl,=buty1 pentyl, hexyl, heptyl, nonyl, decyl, hendecyl, dodecyl,octadecyl, etc., and aryl, preferably phenyl;

R represents alkyl, preferably lower alkyl, e.g. methyl, ethyl, propyl,butyl, pentyl, and hexyl, aryl, preferably phenyl, and substituted aryl,preferably substituted phenyl, and alkanoyl, e.g. formoyl, acetyl,propionyl, butyryl, etc., caproyl, lauroyl and stearoyl, etc.; and

Y represents substituted aryl, e.g. substituted phenyl,

preferably hydroxyphenyl.

A third class of new substituted thiazoles comprises compounds of theformula:

wherein:

R represents hydrogen and alkyl having from 1 to 3 carbon atoms, e.g.methyl, ethyl, propyl;

R represents alkyl, e.g. methyl, ethyl, propyl, butyl,

pentyl, hexyl, octyl, dodecyl, octadecyl, etc.; and

X represents substituted aryl, preferably hydroxyphenyl.

A fourth class of new substituted thiazoles comprises compounds of theformula:

S 9 R10 S IV wherein R and R each represents alkyl, e.g. methyl, ethyl,propyl,

butyl, hexyl, octyl, dodecyl, octadecyl, etc., aryl, preferably phenyl,substituted aryl, preferably substituted phenyl, especially alkylphenyl,e.g. methylphenyl, ethylphenyl, propylphenyl, butylphenyl, octylphenyl,dodecylphenyl, octodecylphenyl, etc.;

R and R each represents hydrogen and aryl, preferably phenyl, andpreferably both R and R do not represent aryl, e.g. phenyl, at the sametime;

X represents arylene, preferably phenylene; and

n represents a number selected from the group consisting of 1 and 2.

A fifth class of new substituted thiazoles comprises compounds of theformula:

wherein R represents methyl, ethyl, propyl; and

X represents aminophenyl and alkylhydroxyphenyl, e.g.

methylhydroxyphenyl, ethylhydroxyphenyl, propylhydroxyphe'nyl,butylhydroxyphenyl, octylhydroxyphenyl, dode cylhydroxyphenyl,octadecylhydroxyphenyl, etc. A sixth class of new substituted thiazolescomprises compounds of the formula:

1: R13 VI wherein R represents hydroxy, amino, alkylamino, preferablylower alkylamino, alkyl, e.g. methyl, ethyl, propyl, butyl, octyl,dodecyl, octadecyl, etc., alkanamido, e.g. formamido, acetamido,propionamido, butyramido, caproamido, lauramido, stearamido, etc.;

R represents hydrogen, and, when R represents alkyl,

then R represents hydroxy.

In this specification the term lower alkyl signifies an alkyl grouphaving from 1 to 6 carbon atoms, and the expression -t-" signifies-tertiary-.

The novel substituted Z-aminothiazole compounds disclosed hereinaboveare useful as chemical intermediates, e.g. in the synthesis ofsulfathiazoles. Additionally, some of the substituted Z-aminothiazolesof the invention are useful in muscle relaxant compositions. Also, thenovel Z-aminothiazoles hereinabove described are useful stabilizers forvarious unstable materials.

Up to the present time, the use of the foregoing classes of substitutedthiazoles in stabilizing organic material, e.g. polypropylene, has notbeen known. It has now surprisingly been found that many organicmaterials are stabilized against deterioriation, e.g. oxidative and/orlight induced and/or thermal deterioration, by incorporating therein astabilized quantity of a substituted thiazole according to the presentinvention.

The substituted thiazoles of the invention are thus also particularlyuseful in stabilizing lubricating oils of various types, includingaliphatic esters, polyalkylene oxides, silicones, esters of phosphoricand silicic acids, highly fluorine-substituted hydrocarbons, etc.

The substituted thiazoles of the present invention are also useful instabilizing fatty materials, including oils of animal and vegetableorigin which tend to deteriorate, e.g. on standing and exposure toatmospheric oxygen; also saturated and unsaturated hydrocarbons whichtend to deteriorate on storage, such as e.g. gasolines, both natural andsynthetic, in particular, saturated and unsaturated gasolines, etc.; jetfuel, diesel oil, mineral oil, fuel oil, drying oil, waxes, resins, etc.

A particularly effective stabilizer of the invention is2,2-imino-bis-4-(p-t-butylphenyl)-thiazole which is especially useful instabilizing polyolefinic materials, e.g. polypropylene. Anotherespecially valuable stabilizer is 2- (p-aminoanilino)-4-t-butylthiazolewhich is an effective stabilizer for relatively unstable organicmaterial, e.g. waxes, particularly paratfin wax, hydrocarbon oil ofmineral origin, in particular, mineral oil; gasoline, both natural andsynthetic; oil of animal origin, in particular, lard; oils of vegetableorigin, in particular, cotton seed oil. Still another valuablestabilizer is 2-(m-aminoanilino)- 4-t-butylthiazole which is especiallyeffective in stabilizing polymeric material, e.g. polyethylene andaldehydes, such as heptaldehyde. Other preferred stabilizers are 2- .4(m-hydroxyanilino)- and 2-(p-hydroxyanilino)-4-t-butylthiazole which areparticularly useful in stabilizing elastomers, both natural andsynthetic, e.g. polyisoprene rubber.

The choice of a specific substituted thiazole for stabilization of agiven unstable material will depend upon several factors. Availabilityand cost of raw materials for the manufacture of the stabilizer andeffective inhibitory action of the stabilizer, including duration anddegree of activity, are among the factors which control the choice of aspecific stabilizer for a specific substrate which is normally subjectto oxidative deterioration. Toxicity, color, stability to light andsolubility are also important factors.

In general, the stabilizers of the invention are employed in aconcentration of from about 0.001% to about 5% by weight, preferablyfrom about 0.01% to about 1% by weight, based on the total weight of thestabilized material. The specific concentration used varies with thesubstrate and the stabilizer, but the following generalizations can bemade.

Concentrations of about 0.001% to about 0.1% by weight of theantioxidant in polyethylene are useful. In polypropylene, from about0.05% to about 1% by weight of the stabilizer are used. For polystyrene,from about 0.1% to about 1% by weight is useful. In rubber,concentrations of from about 0.05% to about 1% are useful. In mineraloils, concentrations of from about 0.005% to about 1% by weight ofstabilizer are used. Gasolines are stabilized with from about 0.01% toabout 0.1% by weight of stabilizer, preferably 0.051% by weight. Fattymaterial of animal origin, such as lard, is stabilized with from about0.001% to about 0.1% by weight of stabilizer. Oils of vegetable origin,such as cotton seed oil, are stabilized with from about 0.001% to about0.1% by weight of stabilizer.

Hydrocarbon material, such as cycloolefins, e.g. cyclohexene, isadvantageously stablized with from about 0.001% to about 1% by weight ofthe stabilizers of the present invention. The same concentrations ofstabilizer are used to stabilize aldehydes, such as e.g. about 0.01% byweight of stabilizer in heptaldehyde. High temperature lubricants whichare essential diesters, e.g. diisoamyladipate, are stabilized with fromabout 0.5% to about 5%, preferably about 2% by weight of a stabilizeraccording to the invention.

The compounds of this invention may also be used to stabilize organicmaterial in combination with other addtive agents, such as e.g.antioxidants, pourpoint depressants, corrosion and rust inhibitors,dispersing agents, demulsifiers, antifoaming agents, carbon :black,accelerators and other chemicals used in rubber compounding,plasticizers, color stabilizers, heat stabilizers, UV absorbers, dyesand pigments, etc.

The thiazoles of the invention which are useful as stabilizers areprepared advantageously by the reaction of arylthioureas withhalocarbonyl compounds, as in reaction (1) below. Alternatively, anarylamine is reacted with a Z-aminothiazole to produce aZ-arylaminothiazole according to reaction (2) below. Still further, anarylamine can be reacted with a 2-halothi'azole according to reaction(3) below.

N-C-R A fourth alternative synthesis includes the folio ing TABLEIIContinued reaction:

1 Aryl's'ubstrtuent M.P., C. Literature reference R C=O OH 161 MasaoShImotani, Loe. Cit.

l N-C-R 5 R' H-SCEN Ar-NH; Ar-NH-ll g OH 214 Do In the foregoingreaction schemes, X stands for halogen; Ar represents aryl; and R and Rare any suitable group in accordance with the desired compoundsaccording to the present invention.

The sources of the a-halocarbonyl compounds of re action (1) areillustrated below in Table I.

The aromatic thioureas which are used to prepare some of the compoundsof the invention are made by .known procedures involving the reaction ofaromatic amines with either sodium, potassium or ammonium thiocyanatesin (B I 176 Beyerman and Bontekoe, Rc.

Trav. ehim. 72, 643-52 (1953) (C.A. 1954 9966a).

180-181 K. S. Bhatki and M. B.

Kabadi, J. Univ. Bombay fiiis, 17-21 (1956) (CA. 1957 acidic media:

.......... Ryohei Ode and Ryoichl Sakurei, J. Chem. Soc. Japan, Ind.Chem. Sect. 53, 200-2 (1950) (0.1.. 1953 3258b) wherein Ar is anaromatic nucleus which may be substituted or unsubstituted, and M is thesodium, potassium or ammonium ion. A substantial number of thesethioureas have been previously characterized in the literature, e.g. asshown in Table 11, whereas Table III illus- 132433 Wang Scienfla 8mmtrates some intermediates not previously characterized in (Peking) 3,301-4 (1954), the literature (0.11. 1956 8496a).

TABLE I la-Halocarbonyi compounds used as intermediates in theinvention] Compound Structure Reference or source il-bromo-3,3-dimethy1butanone-2 (OH;);C--C-CHz-Br J. B. Dickey et al. J.Org. Chem. 20 499-500 (1955).

ll l-bromotridecanone-Z CH3 CH2 1UCCH2BI Lutz et al., J. Org. Chem. 12

a-Bromoheptaldehyde CH3(CH;)CHCHO Yanovskaya et al. J. Gen.

1 Chem. (USSR) 22 1598-1602 Br (1952) (C.A. 1953 0257).

4,4-dimethyl-3chloropentanone-2 (CHmG CHCCH; Fierens, Bull. Soc. Chim.

. Belg. 64772 1955 p-t-Butyl-phenacyl chloride C1CHrC O t-Cdi Bitter andSokol, J. Am.

Chem. Soc. 70 3419-21 (1948).

p-n-Dodeeylphenacyl chloride ClCHzCO 11-01911 Using method of Auers Ber.

v 39 3757 (1906) who prepared p-ethyl-phtinacyi chloride.

TABLE 11 TABLE IIL-AROMATIC THIOUREAS USED AS N-aryl substitutedthioureaicomppurids used as intermediates in the INTERMEDIATES IN THEINVENTION nven 1011 Compound: 7 Melting point C L Aryl substltuent M P Crterature reference y y y p y 2 th1ourea 16O 1611-(p-aminobiphenyl)-2-thiourea 270 NH 167-168 Masao Shimotani, J. Pharm.

2 Soc. Japan 72 328-30 1952) '-P Pf-Plphenylene-brs-Z-throurea 27 019531627111 9- 1-(p-amlxnophenyl)-2-thiourea 198l-phenyl-l,1-p-phenylene-bis-2-thiourea 218l-(p-acetamidophenyl)-2-thiourea 204-205 NH Mesa shlmotanl,1-(m-actamidophenyl)-2-thiourea 194-195 l-(p-lauramidophenyl)-2-thiourea196-208 l-(p-stearamidophenyi)-2-thiourea 202-206 N1121-(p-aminophenyl)-1-methyl-2-thiourea 177-178 The methods of preparingthe compounds of theinveniifi gifigi ggfi; tion will be'more clearlyunderstood from the examples F la Iasi. Studiieercetfifl whichillustrate the invention, but are not meant to limit stiint 4 No. 1-2,234.43 (195 (on, 1956, 15894).

the same thereto. In the examples, temperatures are in de- 7 8 greescentigrade and parts are by weight, unless otherwise (about 75) forseveral hours. The reaction mixture is noted. The relationship of partsby weight to parts by then diluted with 300 parts of water andneutralized with volume is as that of grams to cubic centimeters.saturated aqueous sodium bicarbonate solution and the I product isextracted with ether. After drying the ether solu-2-ARYLAMINO'4-ARYLTHIAZOLES tion over anhydrous sodium sulfate, theproduct is isolated, removing the ether by distillation. The residuefrom ether is recrystallized from isopropanol yielding 22 parts Phenacylchloride (15.4 parts, is dissolved in parts ofz'o'methoxyanilino'ii'phenylthiazole -860) by volume of benzene andadded to a dispersion of 18.2 Examples 2-10.2-substitutedamino-4-phenylthiazoles Example 1.-2- o-rnethoxyanilino)-4-pheny1thiazol parts of o-methoxyphenylthiourea in parts by volume Inan analogous manner to Example 1, the following of ethanol. The reactionmixture is heated at reflux products were made:

ubst. Phenylthiourea Phenacylchloride, Parts parts by ProductCrystallization R by wt. wt. parts by wt. M.P., C: solvent 2 H 16.8 16.419.0 179-180 Benzene.

8 H 16.7 16.1 12.0 163-165 Isopropanol.

4 H 16.7 15.4 15.0 133-135 Benzene.

5 H 16.8 15.4 14.0 123-125 Ethylene chloride.

6 H 16.7 15.4 15.0 -162 Isopropanol.

7 11.0 6.20 14.9 152-153 Benzene.

OH 8 li-CJI Q-fi-CJI. H 5 2. 74 4. 0 192-194 Petroleum ether.

9 I H 14 7. 7 21. 0 159-160 Benzene-hexane.

t-( aHu (32 s 10 N H 11. 5 7. 7 7. 5 149-150 Benzene.

9 Example 11.-2-p-hydroxyanilino-4-phenylthiazole2-p-hydroxyanilino-4-phenylthiazole parts), melting at 203 uponrecrystallization from isopropanol, is obtained by reacting 22 parts ofp-aminophenol with parts of 2-amino-4-phenylthiazole hydroiodide in 250parts by volume of ethylene glycol at 185 under nitrogen.

Example 12.2-(p-acetamidophenylamino) 4-phenylthiazole Phenacyl chloride(7.7 parts) is dissolved in 35 parts by volume of benzene and added atroom temperature with stirring to a dispersion ofp-acetamidophenylthiourea (10.5 parts) in methyl Cellosolve (100 partsby volume). The reaction mixture is 'then heated at about 80 (:5) for 4hours, then cooled and filtered. The solid obtained (15.3 parts, 88%) isrecrystallized once from ethanol, having a melting point of 255-257".The hydrochloride, so obtained, is then suspended in 100 parts by volumeof ethanol and brought to pH 8 with saturated aqueous sodiumbicarbonate, stirred for one hour, filtered and washed with water. The2-(p-acetamidophenylamino)-4- phenylthiazole is recrystallizedrepeatedly from isopropanol until a constant melting point of 179-180 isreached.

Example 13.2-(m-acetamidophenylamino)- 4-phenylthiazole This compound ismade substantially as described in Example 12 for the p-acetamidoanalog. The residue from ether weighs 18.5 parts. Recrystallization froma mixture of ethylene chloride and benzene yieldsZ-(m-acetamidophenylamino)-4-phenylthiazole, melting at 145-146.

Example 14.-2- (p-lauramidophenylamino) 4-phenylthiazole This compoundis made substantially as described in Example 12 for the p-acetamidoanalog, by reacting 17.5 parts of 1-(p-lauramidophenyl)-2-thiourea with7.7 parts of phenacyl chloride. After neutralization with aqueous sodiumbicarbonate, the product is extracted with chloroform. The2-(p-lauramidophenylamino)-4-phenylthiazole is isolated by distillationof the solvent. After recrystallization from benzene, the2-(p-lauramidophenylamino) 4-phenylthiazole melts at 150-151.

Example 15.2-(p-lauramidophenylamino)4-p-tbutylphenylthiazole Thiscompound is made substantially as described in Example 14 for2-(p-lauramidophenylamino)-4-phenylthiazole by reacting 17.5 parts ofl-(p-lauramidophenyl) 2-thiourea with 10.5 parts of p-t-butylphenacylchloride. The 2 (p-lauramidophenylamino)-4p-t-butylphenylthi azole, thusobtained (17.3 parts) melts at 163.5l64.5 after recrystallization frombenzene.

Example 16.-2- (p-stearamidophenylamino) 4-phenylthiazole This compoundis made substantially as described in Example 12 for the p-acetamidoanalog, by reacting 15 parts of 1-(p-stearamidophenyl)-2-thiourea with5.3 parts of phenacyl chloride. The 2-(p-stearamidophenylamino)4-phenylthiazole is isolated by filtering and drying the precipitateobtained on neutralization with aqueous sodium bicarbonate. Afterrecrystallization from chloroform, the 2 (p-stearamidophenylamino)-4-phenylthiazole (12.6 parts) melts at 146147.5.

Example 17 .2- (N-lauroyl-2-hydroxy-5-t-octylphenylamino)-4-phenylthiazole 3.1 parts of lauroyl chloride, dissolved in 15 partsby volume of dioxane, are added dropwise at 28 during 10 minutes to asolution of 5.5 parts of the compound described in Example 9 and 1.1parts of pyridine dissolved in 35 parts by volume of dioxane. Thereaction mixture is heated at 35 to 40 for 1 hour and then poured into300 parts of water. The dispersion is extracted with ether and driedover anhydrous sodium sulfate. The residue, after distillation of theether (7 parts), is crystallized successively from 75 parts by volume ofhexane, contain ing 5 parts of benzene, from carbon tetrachloride, andfrom hexane. The2-(N-lauroyl-2-hydroxy-5-t-octylphenylamino)-4-phenylthiazole, thusobtained, melts at 106.5 108.

If, in Example 17, acetyl chloride (1.09 parts) is substituted forlauroyl chloride, then 2-(N-acetyl-2-hydroxy-S-t-octylphenylamino)-4-phenylthiazole is obtained.

If, in Example 17, stearoyl chloride (4.23 parts) is substituted forlauroyl chloride, then 2(N-stearoyl-Z-hydroxy-S-t-octylphenylamino)-4-phenylthiazole isobtained.

Example l8.-2- (p-acetamidophenylamino)-4- (p-tbutylphenyl -thiazoleThis compound is made using p-t-butylphenacyl chloride, described byRitter et al., J. Am. Chem. Soc. 70 3419 (1948), the other reagentsbeing the same as described in Example 12. The reaction is run under thesame conditions as above (4 hours i5"). Filtration yields 16.5 parts ofsolid. In this case the free amine is obtained directly.Recrystallization from aqueous ethanol yields 2(p-acetamidophenylamino)-4- (pt-butylphenyl)- thiazole, having a meltingpoint of 198-200".

Example 19.-2- (m-acetamidophenylamino) -4- (p-tbutylphenyl -thiazoleThis compound is made substantially as described in Example 18 for thep-acetamido analog. The residue from a mixture of ethylene chloride andbenzene yields a product melting at 139-140".

Example 20.2-(a-naphthylamino)-4-(p-t-butylphenyl)- thiazolep-t-Butylphenacyl chloride (11 parts) is dissolved in 35 parts by volumeof benzene and added to a dispersion of 10 parts of a-naphthylthioureain 150 parts by volume of ethanol over a period of 20 minutes at 50. Thereaction mixture is then heated at reflux (about 75) for 3 hours,diluted with about 500 parts of Water, then made alkaline with parts byvolume of 10% aqueous sodium hydroxide and finally extracted first withether and then with benzene. The combined extracts are dried overanhydrous sodium sulfate. The residue obtained by distillation of thesolvent at reduced pressure (10 parts), is recrystallized from benzene.Z-(a-naphthylamino)-4-(p-t-butylphenyl)- thiazole is obtained as whitecrystals melting at 214-215 Example 21.-2-(p-diethylaminoanilino)-4-(p-t-butylphenyl) -thiazole p-t-Butylphenacyl chloride (13.0 parts) isdissolved in 25 parts by volume of benzene and added to 13 parts ofp-diethylaminophenylthiourea dispersed in 100 parts by volume of ethanolover a period of 10 minutes at 50. The reaction mixture is heated atreflux for 3 hours, diluted with about 300 parts by volume of water andmade basic with 50 parts by volume of 10% aqueous sodium hydroxide. Theprecipitate is filtered, washed with ether to give 18 parts of2-(p-diethylaminoanilino)-4-(p-t-butyl phenyl)-thiazole, melting at 230.The product is crystallized from benzene and melts at 231233, asslightly offwhite crystals.

Example 22.2-[ (p-anilino -phenylan1ino] 4- (p-t-butylphenyl) -thiazolep-t-Butylphenacyl chloride (10.5 parts) is dissolved in 25 parts byvolume of benzene and added dropwise at 28 over a period of 10 minutesto a dispersion of p-(anilino)- phenylthiourea in 77 parts by volume ofmethyl Cellosolve. The reaction mixture is heated at 80 for 3 /2 hours,cooled and diluted with 100 parts by volume of 5% aqueous sodiumbicarbonate, the precipitated product being extracted With ether. Theether extract is washed with Water, dried over sodium sulfate, the otherbeing removed by distillation at about 15 mm. Hg pressure. The2-[(panilino) phenylamino]-4-(p-t-butylphenyl)-thiazole (19 parts),crystallized from isopropanol, melts at 162-163.

Example 23.2- (p-amino-N-methylanilino)-4-(p-tbutylphenyl) -thiazole Toa solution of 7.83 parts of 1-(p-aminopheny1)-1- methyl-2-thiourea in100 parts by volume of methyl Cellosolve at 7075 is added a solution of9.1 parts of p-tbutylphenacyl chloride in 35 parts by volume of benzeneover 15 minutes, The reaction is essentially complete after 3.5 hours at70-75 After cooling, the reaction is neutralized with aqueous sodiumbicarbonate and the product is isolated by extraction with ether. Theresidue (15.9 parts), after removal of the ether, is recrystallizedsuccessively from a solvent mixture of benzene and hexane, andthereafter from ethanol. The2-(p-amino-N-methylanilino)-4-(p-t-butylphenyl)-thiazo1e, so obtained,has a melting point of 161-162.

If, in Example 23, 1-(p-aminophenyl)-1-hexyl-2-thiourea (15.1 parts) issubstituted for l-(p-aminophenyl-lmethyl)-2-thiourea, then2-(p-amino-N-hexylanilino)-4- (p-t-butylphenyl)-thiazole is obtained.

Example 24.2- [4- (p-aminophenyl)-phenylamino]-4-(p-t-butylphenyl)-thiazole p-t-Butylphenacyl chloride (4.2 parts) isdissolved in 21 parts by volume of benzene and added dropwise over aperiod of 10 minutes at 28 to a dispersion of 4-(p-aminophenyl)-phenylthiourea (6 parts) in 72 parts of methylCellosolve. The dispersion is heated for 6 hours at 80, then dilutedwith 100 parts by volume of aqueous sodium bicarbonate and extractedwith ether. The product. after removal of ether at 15 mm. Hg pressure,weighs 7 parts and is crystallized successively from benzene, a mixtureof isopropanol-benzene, and benzene once again. The2-[4-(p-aminophenyl)-phenylamino] 4 (p-t-butylphenyl)-thiazole, soobtained, melts at 187188.

Example 25 .2- p-amino anilino) -4- (p-n-dodecylpheny1)-thiazolep-n-Dodecylphenacyl chloride (8.1 parts), obtained according to Auer[Ber. 39 3757-64 (1906)] using ndodecylbenzene, is dissolved in 25 partsby volume of benzene and added to a dispersion of 4.2 parts ofp-aminophenylthiourea in parts by volume of ethanol. The reactionmixture is heated at reflux (75 over a period of 2 hours in a nitrogenatmosphere. The reaction mixture is neutralized with base, extractedWith ether, the ether extract being washed with water and then died overanhydrous sodium sulfate. The residue, obtained after distillation ofthe ether (10 parts), is recrystallized from isopropanol. TheZ-(p-aminoanilino) 4 (p-n-dodecylphenyl)-thiazole, thus obtained, meltsat 121.

If, in Example 25, 3-t-butyl-4-hydroxyphenylthoiurea (5.3 parts) issubstituted for p-aminophenylthiourea, then2-(3-t-butyl-4-hyclroxyphenyl) 4 (p-n-dodecylphenyl)- thiazole isobtained.

If, in Example 25, 3-n-dodecyl-4-hydroxyphenylthiourea (8.4 parts) issubstituted for p-aminophenylthiourea, then2-(3-n-dodecyl-4-hydroxyphenyl) 4 (p-n-dodecylphenyl)-thiazole isobtained.

If, in Example 25, 3-n-octadecyl-4-hydroxyphenylthiourea (10.5 parts) issubstituted for p-aminophenylthiourea, then2-(3-n-octadecyl-4-hydroxyphenyl)-4- (p n-dodecylphenyl)-thiazole isobtained.

If, in Example 25, p-n-octadecylphenacyl chloride 10.2 parts) issubstituted for p-n-dodecylphenacyl chloride, then2-(p-aminoanilino)-4-(p-n-octadecylphenyl)-thiazole is obtained.

Examples 26-3 0.Substituted 2-amino-4-p-n-dodecylphenylthiazoles Inanalogous manner to Example 25 the following compounds were prepared:

Subst. phenylthiourea B 1 I; Dodeeyl- X-NR- NHa phenacylchloride,Product X R Parts parts by yield,

by wt. wt. parts by wt. M.P., C. Crystallization solvent Ex. No.

26 H 5 8.1 9.0 Isopropnnoi.

27 H 4.2 8.1 10.0 136-137 Benzene.

28 H 4.6 8.1 11.5 106 Benzene-hexane.

29 H 5 8.1 3 122-124 Isopropanol.

30 HzN H 7. 29 9. 6 2. 9 -175 Isopropanol chlorofor eav- 13 IZ-ACENAPHTHYLAMINO SUBSTITUTED THIAZOLES Example 3 l .2-S-acenaphthylamino) -4- (p-t-butylphenyl) -thi azole p-t-Butylphenacylchloride (10.5 parts), dissolved in 25 parts by volume of benzene isadded dropwise at 27 over a period of 10 minutes to a dispersion of 11.4parts of l-(5-acenaphthyl)-2-thiourea in 75 parts by volume of ethanol.The reactants are heated at 75 for 3 hours and then diluted with about300 parts of water. The resultant aqueous dispersion is neutralized withaqueous ammonium hydroxide to pH 9 to 10 and extracted several timeswith benzene, the combined extracts being washed with water and thendried over anhydrous sodium sulfate; the sodium sulfate is filtered 01fand the filtrate is distilled. During the removal of benzene bydistillation at about mm. Hg pressure, the2-(S-acenaphthylamino)-4-(p-tbutylphenyl)-thiazole separates (14 parts),melting at 196198. On recrystallization from a solvent mixture ofbenzene and hexane, theZ-(S-acenaphthylamino)-4-(p-tbutylphenyl)-thiazole melts at 198-200.

2,2'-IMINO-BIS,(4-SUBSTI'IUTED TH IAZOLES) Example32.2,2'-imino-bis-4-(p-t butylphenyl)- thiazole p-t-Butylphenacylchloride (21 parts) is dissolved in 35 parts by volume of benzene andadded dropwise at 55 1 4 Example 33.2,2'-imino-bis-(4hendecylthia2ole)a-Bromotridecanone (11.1 parts), dissolved in parts by volume ofbenzene, is added over a period ofl5 minutes at 28 to a dispersion ofdithiobiuret (2.7 parts) in 100 parts by volume of ethanol containing3.2 parts of pyridine. The reaction temperature during addition rises toa maximum of 32, whereupon the reaction mixture is heated at reflux(about 75) for two hours. The reaction mixture is diluted with about 200parts of water and extracted with ether, the ether extract being washedwith water and aqueous sodium bicarbonate and dried over anhydroussodium sulfate. The product (10 parts), obtained by distillation of thesolvent, is dissolved in hexane and filtered free of a minor amount ofhexane-insoluble material. The hexane filtrate is treated twice withactivated carbon and the 2,2-imino-bis-(4-hendecylthiazole) crystallizeson cooling, melting at 79-80". After recrystallization from isopropanol,the 2,2-imino-bis- (4-hendecylthiazole) melts at 80-81".

Examples 34-35.--2,2'-imino-bis-(4-substituted thiazoles) The followingcompounds were prepared in a manner analogous to Example 32:

2,4-dlthloa-Haloketone Product yield biuret, parts by Parts PartsCrystallizawt. by wt. R by wt. M.P., C. tion solvent Ex. No.

34. 6.7 a-Bromoplnaeolone. 17.9 (CHmC- 13 114-115 Ethanol water.

35 3. 5 p-n-Dodeeylphenaeyl ehlorlde.. 16.2 I 11. 5 104-105 Isopropanol.

to a dispersion of 6.7 parts of 2,4-dithiobiuret in 100 parts by volumeof ethanol. The reaction mixture is heated at reflux (75) for 3 hours ina nitrogen atmosphere. The reaction mixture is then diluted with 300parts of water and treated thoroughly with saturated sodium bicarbonate(about 200 parts). The aqueous dispersion is extracted with ether, theether extract being washed with water and dried over anhydrous sodiumsulfate. The residue, obtained on distillation of the ether (26 parts),is recrystallized from a solvent mixture of benzene and isopropanol. The2,2, imino-bis-4-(p-t-butylphenyl)- thiazole, so obtained, melts at256257.

If, in Example 21, p-n-octadecylphenacyl chloride (40.6 parts) issubstituted for p-t-butylphenacyl chloride, then 2,2'-imino bis 4(p-n-octadecylphenyl)-thiazole is obtained.

2-ARYLAMINO-4-ALKYL TI-IIAZOLES Example 36,-2-(p-aminoanilino)-4-methylthiazole Chlorophopanone -(7 parts) isdissolved in 25 parts by volume of benzene and added to a dispersion of12 parts of p-aminophenylthiourea in 150 parts by volume of ethanol. Thereaction mixture is heated at reflux (about 75) for several hours. Thereaction mixture is then neutralized with saturated sodium bicarbonatesolution, and the product is extracted with ether. After drying theether solution over anhydrous sodium sulfate, the product is isolated byremoving the ether by distillation. The residue from ether weighs 7parts and is recrystallized from benzene. The2-p-aminoanilino-4-methylthiazole, so obtained, melts at '141.

If, in the foregoing Example 36, l-chlorooctanone-Z (6.5 parts) issubstituted for chloropropanone, then 2-(paminoani1ino)-4-hexylthiazoleis obtained.

Examples 37-40.Substituted 2-amino-4- methylthiazoles The followingcompounds were prepared in an analogous manner to Example 36:

butanone-Z, then Z-(p-aminoanilino)-4-octylthiazole is obtained.

Subst. Plenylthiourea Ex. N0. l-ehioro- Product propanone, yield, Partsparts parts Crystallization X R by wt by wt. by wt M.P., C. solvent 37 H18. 0 10. 0 4. 0 147-148 IsopropanOl.

38 H 16. 7 9. 2 Liquid analysis OH 39 Q E 11. 0 3. 6 11. 0 158-160Cyclohexane 40 (CHmC -C(CH;); H 5. 0 1. 7 4. 0 174-175 Benzenehexane.

1 Calculated: C, 58.53%; H, 5.38%; N, 20.48%. Found: C, 58.32%; H,5.70%; N, 20.24%.

Example 41.2-(p-aminoanilino)-4-t-butylthiazole1-bromo-3,3-dimethylbutanone-2 (9.0 parts), whose preparation isdescribed by J. B. Dickey et al., J. Org. Chem. 499-500 (1955), isdissolved in parts by volume of benzene and is added to a dispersion ofpaminophenylthiourea (9.0 parts) in 75 parts by volume of ethanol atabout over a period of about 10 minutes. The reaction mixture is heatedat reflux for 3 hours, neutralized with base and extracted with ether,the ether extract being dried over anhydrous sodium sulfate. The residueobtained after distillation of the ether weighs 16.9 parts and isrecrystallized from benzene. The 2-(paminoanilino)-4-t-butylthiazole,thus isolated, melts at '17 18 Examples 42-52 .--SubstitutedZ-amino-4-t-br1tYl- Example 53.- 2-(o-hydroxyphenylamino)-4-n-hendecy1-thiazoles I 1 1 thiazole .N-t-C1H1 1-bromotridecan0ne-2 (6.9 parts),whose preparation P 5 is described by Lutz et al. J. Org. Chem. 12 767(1947) is dissolved in parts by volume of benzene and is i v added to adispersion of o-hydroxyphenylthiourea (4.5 The following compounds wereprepared in a manner parts) in parts by volume of ethanol at 49-50 overanalogous to p 411 1 a period of 5 to 10 minutes. The reaction mixtureis Substi. Phenylth iourea l6 1'- bromo-3,3- XNR-- NH1 dimethyl- Productv butanone-z, yield, I

' parts parts M,P., Crystallization by wt. by wt. C. solvent L 9L01112.4 -115,.5..Benzene.

00,. 14.5 178-170 Do; o. v

0.0 11.5 Liq.

9.0 11.0 117-119 Henna-benzene.

17,9 17.6. Y 149-151 Benzene:

8.0 13.0 @0-90 Petrol. ether-hexane.

48 g H 14.0 8.9 18.5 128-129 Benzene-hexane. v i

t-aHn V 1 y 1 V v i 40.-.. V H 5.0 s.2 "5.0 113-114 PetroLeth'er.

12.2 8.9 10.0 161-1625waterisopropanol.

52 H 10.7 17.0 15.0 101-102 Carbon tetrachloride.

Examples 54-59.Substituted 2-amino-4- hendecylthiazoles N C-Il-CnHn Thefollowing compounds were prepared in a manner analogous to Example 53:

Subst. Phenylthlourea tion is neutralized with aqueous sodiumbicarbonate. The precipitated base is extracted with ether, the etherextract being dried over anhydrous sodium sulfate. The sodium sulfate isfiltered'off and the ether removed by distillation. The residue isrecrystallized from a solution of benzene and hexane, yielding pure2-p-hydroxyanilino-5-n-penty1- thiazole, melting at 105-106".

Example 61.--2-o-hydroxyanilino-S-n-pentylthiazole u-Bromoheptaldehyde(9.65 parts), as prepared and described by Yanovskaya et al., J. Chem.(U.S.S.R.) 22 1598-1602 (1952), CA. 47 9257 (1953), is dissolved inparts by volume of benzene and added dropwise at 25-30 over a period of10 minutes to a dispersion of 8.4 parts of o-hydroxyphenylthiourea in 75parts by volume of ethanol. The mixture is heated at reflux in anitrogen Ex. (l! N o. X-NR- NH:

l-bromo- Product X R Parts trldeeanone-2, yield, parts M.P.,Crystallization by wt. parts by wt. by wt. C. solvent 54 H 4. 5 6. 9 7.5 93-94 Hexane.

ONE:

55 H 4. 5 6. 9 5. 2 -71 Carbon tetrachloride.

N HQ

56 H 4. 5 6. 9 8. 0 85-86 Hexane.

O0 CH;

58 H 4. 5 5. 9 9.0 58-60 Petrol ether.

0 CHPO H 2. 9 4. 0 5. 4 58-60 Isopropanol.

Z-ARYLAMINO-S-ALKYL THIAZOLES Example60.2-p-hydroxyanilino-5-n-pentylthiazo1e a-Bromoheptaldehyde (9.65parts), as prepared and described by Yanovskaya et al., J. Gen. Chem.(U.S.S.R.) 22 1598-1602 (1952), CA. 47 9257 (1953), is dissolved in 25parts by volume of benzene and added dropwise at 25-30 over a period of10 minutes to a dispersion of 8.4 parts of p-hydroxyphenylthiourea inparts by volume of ethanol. The mixture is heated at reflux in anitrogen atmosphere for 2 hours. The yellow reaction solution is thendiluted with 150 parts by volume of water containing about 5 parts ofsodium bicarbonate and thoroughly extracted three times with parts byvolume portions of ether. The combined ether extracts are washed withparts by volume of water and dried over anhydrous sodium sulfate. Theresidue, obtained after the distillation of the ether, (10 parts) isdissolved in ethanol, treated with gaseous hydrogen chloride whilecooling, whereupon 7.5 parts of the hydrochloride of2-p-hydroxyanilino-5-n-pen tylthiazole crystallize. This hydrochloridemelts at 152- 154. 7 parts of the hydrochloride are dispersed in waterwith sufiicient ethanol to give a clear solution. The soluatrnospherefor 2 hours. The reaction solution is then diluted with 150 parts byvolume of water containing 5 parts of sodium bicarbonate and thoroughlyextracted in 5 3 portions of 80 parts by volume of ether. The combinedExample 62.2-o-hydroxyanilino-4-methyl-5-tbutylthiazole4,4-dimetl1yl-3-chloropentanone-2 (5.0 parts), as described by Fierens,Bull. Soc. Chim. Belg. 64 772 (1955),

is dissolved in 25 parts by volume of benzene and added dropwise at 2530to a dispersion of o-hydroxy-phenylthiourea (5.6 parts) in 75 parts byvolume of ethanol. The reaction mixture is heated at reflux (75") undernitrogen for 2 /2 hours. The clear yellow reaction solution is 22 partsby volume of ether. The combined ether extracts are washed with 200parts by volume of water, and filtered to remove a small amount ofinsoluble precipitate. The clear ether solution is dried over anhydroussodium sulfate and the desired product (14 parts) is isolated by dilutedW 150 Parts of Water cofltalnlng Parts of recovery of the residue upondistillation of the ether. The sodium bicarbonate and extracted with 3portions of 70 MN p phenylene bis (2 amino 4 t but 1- P4rts y vohmfe offither- Th9 ether efmact 1s f fi Over thiazole) is purified bysuccessive crystallization from anhydrous sodium sulfate. The ether isthen distilled off lLdichlorethane and benzene and has a melting point fand the residue (3.0 parts) is recrystallized from 1:1 iso- 1O 2 P P l'f Yielding unreacted P- Y Y' In a fashion similar to Example 63, otherN,N'-pph nyl r The fes ldll e from the filtrate 1S fi iphenylene-bis-(2-amino-4-substituted thiazoles) are made lized fromn-hexane, yielding pure 2-o-hydroxyan1l1no-4- as f llmethylj5-t-blltylthlalole, meltlPg at If, in Example 63,l-chlorotetradecanone-Z (19.7 parts) m f p fi2,2'd1metPY1'3'chlorodecanon'4 5 is substituted for1-bromo-3,3-dimethylbutanone-2, then (7.4 parts) substituted for4,4d1methyl-3-chloropenta- N,N' p phenylene bis (z amino 4dodecylthiazole) is none-2, then2-o-hydroxyamlmo-4-hexyl-5-t-butylth1azole tained is obtained. If, inExample 63, l-chloroeicosanone2 (26.4 parts) fi fp 62,2,2'dm1eth31-3jchlomoctadecanone'4 is substituted for1-bromo-3,3-dimethylbutanone-2, then (11.2 parts) is substituted for4,4-d1methyl-3-chloropenta-N,Nflp-phenylene-bis-(2-amino-4-0ctadecylthiaz0le) is obnone-2, then2-0-hydroxyaml1no-4-dodecyl-5-t-butylth1aa zole is obtained. E 1 64 67If, in Example 62, (2,2-dimethyl-l-chloropropyl)-octaxamp es decylketone(12.8 parts) is substituted for 4,4-dimethyl-3- In like manner,analogous to Example 63, other N,N'- chloropentanone-Z, then2-o-hydroxyanilino-3-octadecylphenylene bis (2 amino 4 substitutedthiazoles) S-t-butylthiazole is obtained. were made as follows:

Product R1C--N N-CR Subst. phenylthiourea II I ll ll H-C NR NR- H H S SX-NR-C-NHz Parts a'Haloketone, 7 Parts M.P., Crystallization X R by wt.parts by wt. R1 by wt. C. solvent EX T H 11.3 ClCHzCOCHs, 9.2 CH3 5227-229 Methanol isopropanol.

65 H 5.5 010112006113, 5.0 on; 1.3 167-168 Isopropanol.

i IG-NH2 A 66 H 11.3 CICHzCOCsHs, 15.4 CuHs 15 135-136 Carbontetrachloride.

67 H 24 CICHzCOCaEk, 31 00115 31 228-229 Isopropanol.

N,N'-PHENYLENE-BIS-(2-AMINO-4-SUBSTITUTED THIAZOLES) Example63.N,N'-p-phenylene-bis-(2-amino-4-t-butylthiazole)1-bromo-3,3-dimethylbutanone-2 (15.0 parts), as described by I. B.Dickey et al., J. Org. Chem. 20 499-500 (1955), is dissolved in.25 partsby volume of benzene and the benzene solution is added dropwise at to adispersion of p-phenylenedithiourea (9.0 parts) in 100 parts by volumeof methyl Cellosolve over. a period of 20 minutes. After the addition,the reaction mixture becomes homogeneous and is heated at reflux for 4/2 hours in a nitrogen atmosphere. The reaction solution is then pouredinto 150 parts by volume of water containing 4 parts of sodiumhydroxide, and is extracted with 4 portions of Example 68.N,N' pphenylene bis (2 amino 4- p-t-butylphenylthiazole p-t-Butylphenacylchloride (21 parts) is dissolved in 45 parts by volume of benzene andadded to a dispersion of 11.5 parts of p-phenylene-dithiourea in partsby volume of ethanol over a period of 20 minutes at 50. The reactionmixture is heated at reflux (74) for 3 hours and then diluted with 100parts by volume of water. The reaction mixture is made alkaline withabout parts by volume of 10% aqueous sodium hydroxide and extracted withether. The ether is then distilled off and the crude residue washed withmethanol; it melts at 250. The N,N'-p-phenylene-bis-(2-amino-4-p tbutylphenylthiazole), so obtained, is recrystallized from ethylenechloride, giving white crystals melting at 253-255".

23 Example 69.-N,N' bis (4 p t butylphenyl 2-thiazolyl)-N-phenyl-p-phenylenediamine p-t-Butylphenacyl chloride (19.0parts) is dissolved in parts by volume of benzene and added dropwise toa dispersion of 13.6 parts of N-phenyl-p-phenylene-dithiourea in 77parts of methyl Cellosolve at 28 over a period of 10 minutes. Thereaction mixture is heated at 80 for 3 hours and diluted with 100 partsof 5% sodium bicarbonate. The reaction mixture is extracted with 4portions each of 80 parts by volume of ether, the combined 24 aqueoussodium bicarbonate. It is then extracted with ether, the ether extractbeing dried over anhydrous sodium sulfate. The residue from ether isisolated by distillation of the ether and is recrystallized fromisopropanol. The 2 o hydroxyanilino-4,5,6,7-tetrahydrobenzothiazolemelts at 191192.

Examples 71-73 The following 2-substitutedaniline-4,5,6,7-tetrahydrobenzothiazoles were made using the sameprocess as in Example 70:

72 16. 7 13. 0 6 184 Isopropanol.

13. 2 8 164-165 Benzene.

2 ARYLAMINO TETRAHYDROBENZO- THIAZOLES Example70.2-o-hydroxyanilino-4,5,6,7-tetrahydrobenzothiazole2-chlorocyclohexanone (13 parts) and o-hydroxyphenylthiourea (16.8parts) are dispersed in 150 parts by volume of ethanol, and thedispersion is heated at reflux for about 3 hours. The reaction mixtureis then diluted with an equal amount of water and neutralized withBIPHENYLENE-B IS- (2-AMINO-4-SUBSTITUTED THIAZOL'ES Example74.N,N'-p-biphenylene-bis-(2-amino-4-tbutylthiazole)1-bromo-3,3-dimethylbutanone-2 (14.3 parts) is dissolved in 26 parts byvolume of benzene and added dropwise over a period of 10 minutes at 27to a dispersion of p-biphenylene-bis(2-thiourea) (12.8 parts) in 127parts by volume of methyl Cellosolve. The reaction mixture is heated atfor 4 hours and then diluted with 300 parts by volume of water,containing 10 parts of sodium bicarbonate, and well agitated. Themixture is extracted with ether, the ether extract being washed withwater and dried over anhydrous sodium sulfate. The ether is distilledoff and the N,N-p-di-phenylene-bis-(2-amino-4-t-butylthiazole) (16parts) is crystallized from a mixture of benzene and chloroform; itmelts at 243-244.

3,467,666 25 26 Examples 75-77 according to Example 78, are incorporatedinto high im- In a similar fashion to Example 74, other N,N'p-bi- Ppolystyr'fne (Foster Grant Tuflex, X11516) y phenylene bis (2 amino 4substituted thiazoles) mg at 1!! an amount of 01% y then the were madeas follows: resultant compositions are stabilized against deterioration.

Product R l3lq I[In-- n a 40H NH NH l l S s C=S C=S Ex. I I No. NHz NH:a-Haloketone R M.P., C. Crystallization solvent Q-o CHzCl 75 12.8 partsby wt 12.3 parts by wt parts by wt 276-278 Pyridine-benzene.

11C12H25 l2 76 6.5 parts by wt 12.9 parts by wt 15 parts by wt 258-263Tetrahydrofuran benzene.

O CH3(CH2)1oCH2Br I1-C11H23 77 6.5 parts by wt 11.1 parts by wt 12 partsby wt 149-151 chloroform.

Example 78 Example 79 Unstabilized polypropylene powder (Hercules ProfaxA stabilized mineral oil composition is prepared by in- 6501) isthoroughly blended with 0.5% by weight of 2,2'- corporating into arefined paraffin-type mineral oil of 183imino-bis-4-(p-t-butylphenyl)-thiazole made according to S.U.S. at 100F. (Regal Oil B, Texas Company) 0.05% Example 32. The blended materialis then milled on a two by weight of the stabilizer2-(p-aminoanilino)-4-t-butylroller mill at 182 for 10 minutes, afterwhich time the thiazole (Example 41). The stability of this compositionstabilized polypropylene is sheeted from the mill and alis tested byincorporating therein 20 parts per million of lowed to cool. solublecopper as the naphthenate and placing the result- The milledpolypropylene sheet is then cut into small ant mixture in a modifiedSligh oxidation flask equipped pieces and pressed for 7 minutes on ahydraulic press at with a mercury manometer (Davis et al., Ind. Eng.Chem., 218 and 2000 pounds per square inch pressure. The re- 33 339,March 1941). The flask is maintained in a consultant sheet of 25 milthickness is then tested for resiststant temperature oil bath at 115.The length of time for ance. to accelerated aging in a forced draft ovenat 149. a pressure drop of 60 mm. from the maximum pressure As evidentfrom the table below, the composition of 0.5% noted is taken as the timeof failure. The stabilized minby Weight of 2,2 iminobis-4-(p-t-butylphenyl)-thiazole oral oil does not fail after 96 hours,the blank failing afand polypropylene is stabilized againstdeterioration. ter only 3 /2 hours.

STABILIZATION OF POLYPROPYLENE AGAINST OVEN ia the fqregoing QQnditionsof Example AGING AT 149CRAZING1 TIME eral 011 IS etfectively stabilizedalso by each of the follow- Houl's ing compounds: Polypropylene alone 3Polypropylene+0.5% stabilizer 500 p l no)-4-p y a p 1 Grazing is thesurface embrittlement (fine cracks on surl l i f (Example 6) face) whichis an indication of oxidative deterioration.2-(p-ammoanil1no)-4-n-hendecylth1azole (Example 55)22'2"iminbiS'4(p't'butylphenyl)'thlazole (Example 32)N,N'-o-phenylene-bis (2-amino-4-methylthiazole) (Exam- Other substitutedthiazoles which are also eifective at ple 0.5% by weight inpolypropylene are:

2,2-imino-bis-(4-hendecylthiazole) (Example 33) 2-(N-phenyl-p-hydroxyphenylamino) -4-phenylthiazole (Example 7)2-(ot-naphthylamino)-4-n-hendecylthiazole (Example 59)2-(u-naphthylamino)-4-(p-t-butylphenyl)-thiazole (Example 20) N,N'-bis-(4-p-t-butylphenyl-2-thiaz olyl) -N-phenyl-pphenylenediamine (Example69) 2 (N-lauroyl-Z-hydroxy-5-t-octylphenylamino -4- phenylthiazole(Example 17) Example 81 In like manner, if eitherZ-(m-aminianilino)-4-t-butyl- Stabilized lard is prepared byincorporating in lard thiazole (Example 52) or2-(m-aminoanilino)-4-phenyl- (Tobin Packing Co.) 0.01% by weight ofZ-(p-aminothiazole (Example 6) is incorporated into low-pressureanilino)-4-t-butylthiazole (Example 41). The lard, with polyethylene inan amount of 0.1% by weight, then the and without stabilizer, is testedby the oxygen induction resultant composition is stabilized againstdeterioration. period method (ASTM D525-55) with the following Example80 60 Stabilized gasoline is prepared by incorporating into gasoline,having no additives and no stabilizers therein, 0.05% by weight ofZ-(p-aminoanilino)-4-t-butylthiazole (Example 41). The gasoline, withand without stabilizer, is tested by the oxygen bomb induction periodmethod 65 (ASTM D525-55), with the result that the gasoline withstabilizer has not failed after 500 minutes, while the blank fails after250 minutes.

In like manner also, if all the foregoing compounds modifications: 15parts of lard sample are tested; the

end point is defined as the mid-point of the first hour, in which apressure drop of 2 lbs. per square inch or greater is noted, followed byan equivalent or greater drop in the succeeding hour. The stabilizedlard does not fail after 500 minutes, while the unstabilized lard failsafter 108 minutes.

Lard is also stabilized with each of the following antioxidants:

2-(o-aminoanilino) 4 (n-dodecylphenyl)-thiazole (Example 29)2-(p-aminoanilino)-4-methylthiazole (Example 36) If cotton seed oil(refined, Welch, Holme and Clark) is substituted for lard in theforegoing test and as stabilizer 2-(o-aminoanilino) 4(n-dodecylphenyl)-thiazole (Example 29) is used, then the cotton seedoil containing stabilizer does not fail after 500 minutes, while theunstabilized cotton seed oil fails after 282 minutes.

Example 82 High temperature lubricant (diisoamyladipate) is stabilizedby incorporating therein 2% by weight of 2-(p-aminoanilino)-4-t-butylthiazole (Example 41) into said lubricant. Theresultant stabilized lubricant composition is compared with theunstabilized lubricant by heating at 175 in presence of air and metalliccatalysts according to the test method described in MilitarySpecification Mil-L-7808c. After 72 hours the blank contains 83% sludgeand has increased significantly in acidity. The stabilized lubricant,however, contains less than 15% of sludge and shows no increase inacidity.

Example 83 Heptaldehyde is stabilized by incorporating into the freshlydistilled aldehyde 0.01% by weight of2,2-iminobis-(4-t-butylphenyl)-thiazole (Example 32). The stabilizedheptaldehyde is shaken in an oxygen atmosphere in the dark under normalpressure at room temperature (23). The time necessary for absorption of30 parts by volume of oxygen in 25 parts of heptaldehyde is 89 hours forthe stabilized heptaldehyde, but only A hour for heptaldehyde alone.

Heptaldehyde is also effectively stabilized by each of the followingcompounds: Z-(m-aminoanilino)-4-t-buty1thiazole (Example 52)2'-(o-aminoanilino) tetrahydrobenzothiazole (Example Example 84Cyclohexene, freshly distilled, is stabilized by addition thereto of0.001% by weight of the stabilizer 2-(p-aminoanilino)-4-t-butylthiazole(Example 41). The elfectiveness of this antioxidant in cyclohexene istested by the ASTM D525-55 oxidation test with the modification thatonly parts by volume of cyclohexene are used in each bomb. Thestabilized cyclohexene runs more than 200 minutes without failure, whileunstabilized cyclohexene fails after 30 minutes.

Cyclohexene is also stabilized by each of the following compounds:2-(o-hydroxyanilino)-4-t-butylthiazole (Example 42)2-(p-hydroxyanilino)-4-t-butylthiazole (Example 43)2-(2-hydroxy-5-t-0ctylanilino) 4 t-butylthiazole (Example 48)2-(o-aminoanilino) tetrahydrobenzothiazole (Example In like manner tocyclohexene, tetralin is stabilized with 0.001% by weight of each of thefollowing compounds: 2-(p-aminoanilino)-4-phenylthiazole (Example 4) 2-(p-hydroxyanilino) 4 p-n-dodecylphenylthiazole (Example 27) Example 85Paraffin wax (M.P. 125-l28) is stabilized by incorporating therein0.001% by weight of 2-(p-aminoanilino)- 4-t-butylthiazole (Example 41).The effective stabilization is illustrated by the following odor test:The stabilized paraffin is heated at 121 in the presence of air. A likeamount of unstabilized parafiin wax is also heated under the sameconditions. After 18 hours, there is no preceptible odor for thestabilized wax. The unstabilized wax, however, exhibits a distinct odor.

Paraflin was is also stabilized by 0.001% by weight of each of thefollowing compounds:

Z-(p-aminoanilino)-4-methylthiazole (Example 36) 2-(o-hydroxyanilino) 4p n dodecylphenylthiazole (Example 26) Example 86 Stabilized rubber isprepared by mixing in the cold:

Parts Hevea latex crepe 100.0 Stearic acid 1.5 Zinc oxide 5.0Diphenylguanidine 1.0 Sulfur 2.5

2 (p-hydroxyanilino)-4-t-butylthiazole (Example The resultant mixture isvulcanized at and tested according to ASTM D-1206-53T. The time requiredto elongate a test strip from 120 mm. to mm. is 8 /2 hours for theunstabilized rubber, and more than 35 hours for the stabilized rubber.In a similar way polyisoprene rubber and styrenebutadiene rubber arestabilized.

The rubber of Example 86 is stabilized in like manner, if 1.0 part ofone of the following compounds:

2-(o-hydroxyanilino)4-t-butylthiazole (Example 42); or

Z-(p-hydroxyanilino) 4 (p-n-dodecylphenyl)-thiazole (Example 27 orZ-(p-aminoanilino)-4-phenylthiazole (Example 4) is substituted for 1.0part of 2-(p-hydroxyanilino)-4-t-butylthiazole (Example 43) It isunderstood that in the foregoing Examples 78-86 inclusive, compositionswhich comprise the oxidizable material of each of said examples therein,are stabilized by elfective amounts of the new compounds, preparedaccording to the preceding Examples 1-77 inclusive.

We claim:

1. A compound of the formula:

NCR5 X-NH-ii i-4h s wherein:

R alilsdhydrogen, or an alkyl of 1 to 18 carbon atoms;

R is an alkyl of 1 to 18 carbon atoms; and X is hydroxyphenyl. 2. Acompound of the formula:

8 wherein:

(References on following page) 29 30 References Cited Karrer: OrganicChem. (New York, 1950), pp. 764- UNITED STATES PATENTS 22,219? h l i l"-1 ALEX MAZEL, Primary Examiner 2,3 ,1 iereta. 2,863,874 12/1958Gregory 260-306.8 5 D Asslstant Exammer OTHER REFERENCES us. 01. X.R.

Mahapatra: Chem. Abstracts, vol. 52, pp. 72, 84-5 44-63; 260.453, 398.5(1958).

* P f-{ UNITED STATES PATENT OFFICE QERTIFICATE 0F CORRECTION Patent No.5,+ 7, Dated September 16, 1969 Inventor(s) John D. Spivack GT, 611.

It is certified that error appears in the above-identified patent andthat said Letters Patent are hereby corrected as shown below:

in Column 2, l1. mum, in Formula III, 'C-R' should read In Column 7, l.5, 'phenylthiazol' should read -phenylthiazole- In Column 12, l. 8,died' should read -dried- Tn Column 21, l. 15, 'chlorodecanon' shouldread -chlorodecanone- In Column 25, l. 70 'aminianilino' should read-aminoanilino- SIGNED AND SEALED MAY 191970 Attest:

Attcsting Officer Commissioner of Patents

